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In a sampling distribution of means, what is the mean of sample means equal to?

The population mean (μ)

In sampling distributions, what term and symbol represent variability?

Standard error of the mean (σx̄)

What is the formula for standard error of the mean?

σx̄ = σ / √n

What is the formula for z obtained?

z = (x̄ − μ) / σx̄

If z obtained is small, is probability large or small?

Large probability

If z obtained is large, is probability large or small?

Small probability

What is the standard alpha level?

0.05

For alpha = 0.05 two-tailed, what are critical values?

-1.96 and +1.96

For alpha = 0.05 one-tailed, what are critical values?

-1.645 or +1.645

What does r represent?

Strength and direction of a linear relationship

Which correlation is strongest?

The correlation closest to ±1

Give an example of a positive correlation.

More studying leads to higher test scores

Give an example of a negative correlation.

More water leads to less thirst

What is a curvilinear relationship?

A relationship that changes direction (nonlinear)

What is an outlier?

An extreme unusual score

What is range restriction?

Not measuring the full range of scores

What is Y′ (Y prime)?

Predicted score on Y

What is a residual?

Y − Y′

What does r² represent?

Proportion of variance explained

If r = 0.35, what is r²?

0.1225

Interpret r² = 0.1225.

12.25% of variance in Y is explained by X

Does correlation imply causation?

No

If z is in rejection region, what is true about p?

p < alpha

If z is not in rejection region, what is true about p?

p > alpha

When do you reject H0?

When p < alpha

When do you fail to reject H0?

When p > alpha

Alternative hypothesis symbols?

H1 or Ha

Null hypothesis symbols?

H0

If sample is different from population, which hypothesis?

Alternative hypothesis

If sample is not different from population, which hypothesis?

Null hypothesis

If question says different, one-tail or two-tail?

Two-tailed

If question says greater than or less than, one-tail or two-tail?

One-tailed

If alpha = 0.05 and p = 0.03, do you reject H0?

Yes

Standard error of estimate formula?

SEest = √[Σ(Y − Y′)² / (n − 2)]